In September 1962, shortly before the opening of the Second Vatican Council, Pope John XXIII learned that he had inoperable cancer. Throughout the first session of the council, he knew that his life was drawing to a close.

Archbishop Pedro Ricardo Barreto Jimeno isn't easily intimidated. But when a coffin bearing his name was found inside an American mining firm's closed smelter in La Oroya, Peru, in 2009, he felt a chill in his spine.